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Gents, I'm making a bent laminate arch from Cherry. This will be a catenary arch made by compressing a stack of laminate end-on so that it 'buckles' to the desired shape.
I need about 2" of "rise" over a 36" run, and the final stack will about 1/2" thick. What's thickest I can have the plys and make this work?
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I always go with 1/8". Unless it is a tight radius of course.
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Garry
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I always do what musemguy said, 1/8" and have done 3/16" before too. 2" over a 36" radius is not a very tight bend so you should be fine with either of those thicknesses. I also use plastic resin glue on my bent lams which has a little less springback than pva glue IMHO.
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(03-22-2019, 05:54 PM)FrankAtl Wrote: I always do what musemguy said, 1/8" and have done 3/16" before too. 2" over a 36" radius is not a very tight bend so you should be fine with either of those thicknesses. I also use plastic resin glue on my bent lams which has a little less springback than pva glue IMHO.
And gives you time to fuss.
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(03-22-2019, 04:13 PM)jgourlay Wrote: Gents, I'm making a bent laminate arch from Cherry. This will be a catenary arch made by compressing a stack of laminate end-on so that it 'buckles' to the desired shape.
I need about 2" of "rise" over a 36" run, and the final stack will about 1/2" thick. What's thickest I can have the plys and make this work?
1/4" should bend easily with a 2" rise. If you soak the whole piece in hot water with a Fabric softener then lamination is not needed. Keep the piece in water til it cools , then bend and clamp around a form. Make the form for a 2-1/4" bend, allows for spring back. Leave in form for 24 hrs.
mike
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Thanks Ya'll! Relieved 1/8" will work: makes it easy.
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Please let us know how it turns out (pics or it didn't happen)
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Garry
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(03-22-2019, 04:13 PM)jgourlay Wrote: Gents, I'm making a bent laminate arch from Cherry. This will be a catenary arch made by compressing a stack of laminate end-on so that it 'buckles' to the desired shape.
I need about 2" of "rise" over a 36" run, and the final stack will about 1/2" thick. What's thickest I can have the plys and make this work?
More, thinner laminates spring back less than fewer, thicker laminates.
I tend to use 1/8” to make it easier to determine the final thickness.
You will also need to overbend the stack because it will spring back some when removed from the clamps. For 1/8” thick strips with this bend up, overbend by about 3/4” over the desired radius.
